Idaho ITD CDL General Knowledge Practice Test 7
- Questions50
- Correct to pass40
- Passing score80%
- Minimum age18 years
-
1. You are pulling away from the curb after a delivery. Why is a mirror check needed first?
Show answer
Answer B: A cyclist or a vehicle may be coming up alongside you
Traffic and cyclists can arrive alongside a parked vehicle at any moment, so the mirrors must be checked immediately before pulling out.
-
2. An automatic transmission is left in its normal drive position as the vehicle rolls down a long grade. What does it tend to do?
Show answer
Answer A: Shift up as road speed rises, so engine braking falls away
An automatic left in drive keeps upshifting as speed builds, which is the opposite of what you want on a grade; that is why the driver must select a low range.
-
3. Why must the downshift be finished before you reach a steep downgrade or a sharp curve rather than during it?
Show answer
Answer D: Because once your speed is too high you may not get into any gear at all
If you wait until speed has built up, the lower gear may refuse to engage and you can be left in neutral with no engine braking at all.
-
4. Around a tractor-trailer, where are the blind areas that other drivers most often sit in unseen?
Show answer
Answer A: Along the right side and directly behind the trailer
The blind areas to the right of the cab and behind the trailer are the largest, which is why other drivers should never linger there.
-
5. What is the danger of letting engine speed climb past the top of the rated rpm range before you shift?
Show answer
Answer B: You can damage the engine, so the shift should be made before that point
Every engine has a rated operating range; running above it can cause serious engine damage, so the upshift belongs at the top of that range, not beyond it.
-
6. A straight truck has a long body behind the rear axle. What happens to that overhang in a sharp left turn?
Show answer
Answer D: It swings out to the right and can strike a vehicle or an object on that side
Body that hangs behind the rear axle swings the opposite way to the turn, so the tail of the truck sweeps out into the next lane or over the curb.
-
7. What is the correct order for a basic double clutch upshift?
Show answer
Answer B: Release the accelerator and push the clutch, shift to neutral, release the clutch, let engine speed drop, push the clutch again and shift to the higher gear
Double clutching passes through neutral with the clutch released so engine speed can drop to match the next gear before it is engaged.
-
8. Who must sign a driver vehicle inspection report?
Show answer
Answer D: The driver who prepared it
The report is the driver statement about the condition of the vehicle at the end of the day, so the driver signs it.
-
9. How do you test for leaks in a hydraulic brake system during the pre-trip inspection?
Show answer
Answer A: Pump the pedal three times, then hold firm pressure for five seconds and make sure the pedal does not move
If the pedal sinks while you hold pressure, fluid is escaping or air is in the lines, and the vehicle must not be driven until the problem is repaired.
-
10. A driver snores heavily, stops breathing briefly during the night and is tired all day despite long hours in bed. What should be suspected?
Show answer
Answer B: Sleep apnea
Sleep apnea repeatedly interrupts breathing during sleep, so the driver never gets true rest and stays dangerously drowsy during the day.
-
11. Dry bulk tanks call for extra caution mainly because of what?
Show answer
Answer C: A high center of gravity combined with a load that can shift
Dry bulk loads ride high and can move inside the tank, which makes the vehicle easier to tip in a curve.
-
12. What is checked about the engine cooling system during the engine compartment inspection?
Show answer
Answer C: That the coolant level is adequate and the radiator and hoses are not leaking
A low coolant level or a leaking hose leads to overheating, which can stop the vehicle in a place where stopping is dangerous.
-
13. The shipper hands you the placards for a load that needs them. Who puts them on the vehicle?
Show answer
Answer C: The driver, who must also make sure they are the correct ones and are readable
The shipper supplies the placards, but it is the driver who must place them on the vehicle and confirm that they match the load and can be read.
-
14. An oncoming vehicle drifts across the center line into your lane. What is usually the safest move?
Show answer
Answer C: Steer to the right, toward the shoulder if necessary
Moving right keeps you away from the drifting vehicle and off the oncoming side; the other driver may swerve back and hit you if you go left.
-
15. What is checked in step six of the seven-step method?
Show answer
Answer D: The turn signals and the stop lights, checked from outside the vehicle
Step six returns to the cab to switch on the signal and stop lamps, then checks each one from outside, because those lamps are not lit during the earlier light check.
-
16. Where on the road are you most likely to find ice in cold weather?
Show answer
Answer B: On bridges, overpasses and shaded stretches, which freeze before the rest of the road
Bridges and overpasses lose heat from above and below, and shaded areas get no sun, so they ice over first and stay icy longest.
-
17. What is required of the hooks, rails, rings and anchor points that tiedowns attach to?
Show answer
Answer A: They must be part of the vehicle and strong enough for the load being secured
A tiedown is only as strong as what it is hooked to, so anchor points must be proper vehicle fittings rated for the job.
-
18. What is the first step of the standard seven-step vehicle inspection?
Show answer
Answer C: A general overview of the vehicle, including the last inspection report
The routine opens with a walk-up overview of the vehicle and a review of the previous inspection report so known defects are addressed first.
-
19. Why should a driver avoid stopping partway up a snow covered hill?
Show answer
Answer D: You may not get moving again and could slide backwards
On a slippery grade the drive wheels may simply spin when you try to restart, leaving the vehicle stuck across the road or sliding back down it.
-
20. Your speedometer stops working during the pre-trip check. How should it be treated?
Show answer
Answer D: As a defect, because the driver cannot judge and control speed without it
A working speedometer is required equipment, because judging speed by feel in a heavy vehicle is unreliable and speed governs stopping distance.
-
21. At 55 mph, about how far does a vehicle travel during a typical 3/4 second perception time plus 3/4 second reaction time, before the brakes even begin to work?
Show answer
Answer C: About 120 feet
Each 3/4 second at 55 mph covers about 60 feet, so perception and reaction together use up roughly 120 feet before braking starts.
-
22. Some commodities have their own detailed securement rules on top of the general ones. Which list is made up of such commodities?
Show answer
Answer C: Logs, metal coils, paper rolls, concrete pipe and crushed vehicles
The cargo securement rules add specific requirements for particular commodities, including logs, dressed lumber, metal coils, paper rolls, concrete pipe, intermodal containers, vehicles, crushed cars, roll on containers and large boulders.
-
23. A delivery van is stopped in the right lane ahead with its flashers on. What should you expect?
Show answer
Answer C: Someone may step into your lane from in front of it
A stopped delivery vehicle hides the space in front of it, and that is exactly where a person carrying a package is likely to walk out.
-
24. Most rollovers of loaded trucks on exit and entrance ramps happen for which reason?
Show answer
Answer B: The ramp was taken faster than the load could tolerate
A posted ramp speed is set for cars, and a loaded trailer with a high center of gravity can roll at a speed a car would take easily.
-
25. Under federal safety rules, what must the driver of a commercial vehicle do before starting a trip?
Show answer
Answer A: Be satisfied that the vehicle is in safe operating condition
The driver is responsible for inspecting the vehicle and must be satisfied it is in safe operating condition before the trip begins.
-
26. You are loading lengths of large diameter pipe on a flatbed. What is needed besides the tiedowns?
Show answer
Answer D: Chocks, wedges or cradles that keep the pipe from rolling
Anything that can roll must be prevented from rolling by chocks, wedges, cradles or a similar device that is itself secured so it cannot come out.
-
27. Besides the hours when the law requires them, when should headlights be switched on?
Show answer
Answer A: Any time visibility is poor, such as in rain, fog or at dusk
Headlights are used to be seen as much as to see, so they belong on whenever light or weather makes the vehicle harder to spot.
-
28. What should you do with the previous driver vehicle inspection report before starting your trip?
Show answer
Answer B: Review it and confirm that listed defects were certified as repaired or as not needing repair
Reviewing the last report and the carrier certification tells you whether reported defects have been corrected before you take the vehicle out.
-
29. Why must cargo also be held down against vertical movement and not only against sliding?
Show answer
Answer D: Because a load that bounces can jump the blocking and slacken its own tiedowns
Rough road makes an unrestrained article lift; every bounce lets it move a little and works the tiedowns loose until nothing is holding it.
-
30. Total stopping distance is made up of which parts?
Show answer
Answer A: Perception distance, reaction distance and braking distance
The vehicle travels while the hazard is recognized, while the driver moves to the pedal, and again while the brakes slow the vehicle.
-
31. Federal rules say a commercial vehicle may not be driven unless what is true of its cargo?
Show answer
Answer B: It is properly distributed and adequately secured
The basic federal requirement is that the load be distributed properly and secured well enough that it cannot move, whatever the paperwork says.
-
32. What is the driver responsible for when a load is covered with a tarp?
Show answer
Answer C: Fastening it so it cannot flap free, block a mirror, or come off in the wind
A tarp that works loose can tear away, block the driver view or the view of others, and become a hazard for the traffic behind.
-
33. Where on a tire is tread depth measured?
Show answer
Answer C: In a major tread groove, away from any tie bar or wear indicator
Depth is taken in a major groove and away from the raised tie bars and wear indicators, which would give a shallower and misleading reading.
-
34. Which wheel or rim condition must be treated as a defect during the walkaround?
Show answer
Answer C: Cracks, illegal welded repairs, or missing and loose lug nuts
Cracked or welded rims and missing or loose fasteners can let a wheel separate from the vehicle and must be corrected before driving.
-
35. The coolant temperature gauge climbs above its normal range on a long grade. What is the correct response?
Show answer
Answer C: Stop when it is safe to do so and find the cause before going on
Rising coolant temperature signals a fault such as a lost belt, a leak or a blocked radiator, and continuing can turn a repair into a destroyed engine.
-
36. Your right wheels drop off the pavement onto a soft shoulder. What is the correct recovery?
Show answer
Answer A: Stay on the shoulder, ease off the accelerator, brake gently only once speed is down to about 20 mph, then steer back sharply and countersteer at once
Bringing speed down on the shoulder first avoids a violent sideways jolt, and countersteering the instant the tires are back on the pavement keeps the vehicle out of the next lane.
-
37. Why does a cracked frame rail or cross member make a vehicle unsafe?
Show answer
Answer B: The frame carries the whole load, and a crack can spread until the structure fails
The frame is the backbone that supports the body, the load and the running gear, so a crack in it is a structural failure that grows with every mile.
-
38. You are hauling an open box of loose gravel. What does that load require?
Show answer
Answer A: A cover, so that material cannot blow off or spill onto the road
Loose material that can be blown or spilled has to be covered so it does not come out of the body and strike traffic behind.
-
39. How soon must warning devices be placed after a commercial vehicle stops on the traveled part or the shoulder of a highway?
Show answer
Answer D: As soon as possible and in any case within 10 minutes
The hazard warning flashers go on immediately and the warning devices must be in place as soon as possible, never later than 10 minutes after stopping.
-
40. How long must the record of a periodic inspection be kept?
Show answer
Answer A: Fourteen months
The periodic inspection report is retained for fourteen months from the date of the report, which covers the full twelve month cycle plus a margin.
-
41. The brake pedal goes to the floor in a vehicle with hydraulic brakes. What can you do to build some braking pressure?
Show answer
Answer B: Pump the brake pedal rapidly, which may bring back enough pressure to slow the vehicle
Pumping can restore some hydraulic pressure; along with downshifting and the parking brake it is one of the ways to stop when the pedal fails.
-
42. What are you checking when you pull the engine oil dipstick during the pre-trip?
Show answer
Answer A: That the oil level is within the safe operating range marked on the stick
The dipstick shows whether there is enough oil to lubricate and cool the engine, and a level outside the safe range must be corrected before driving.
-
43. Why should you never shift gears while crossing railroad tracks?
Show answer
Answer A: You could miss the gear or stall and be stuck on the tracks
A stalled or coasting vehicle on the tracks has no way to clear quickly, so choose the gear before the crossing and do not shift until you are across.
-
44. In the seven-step method, what comes immediately after starting the engine and inspecting inside the cab?
Show answer
Answer D: Turn off the engine and check the lights
Step four shuts the engine down and switches on the lamps needed for driving so the driver can leave the cab and confirm they actually work.
-
45. When is tire pressure most accurately compared with the recommended figure?
Show answer
Answer B: When the tires are cold, before the vehicle has been driven
Recommended pressures are cold pressures, so a reading taken before the tires have heated up is the only one that can be compared directly.
-
46. Why does extra weight make a long downgrade more dangerous even when the brakes are in good order?
Show answer
Answer B: Gravity adds to the momentum and the brakes heat up faster
The heavier the vehicle, the more energy the brakes must turn into heat, and heat is exactly what makes brakes fade on a long descent.
-
47. Why do cracked spring hangers or badly worn shackles matter?
Show answer
Answer A: They allow the axle to shift out of its correct position under the vehicle
Hangers and shackles hold the spring, and therefore the axle, in place, so when they fail the axle can move and the vehicle may become uncontrollable.
-
48. An unblocked crate 4 feet long and weighing 900 pounds needs at least how many tiedowns?
Show answer
Answer D: One
An article 5 feet or less in length and 1,100 pounds or less in weight is covered by a minimum of one tiedown.
-
49. What should a driver assume about the height posted at a bridge or an overpass?
Show answer
Answer B: That it may be wrong, because repaving or packed snow can leave less clearance than the sign shows
Resurfacing and packed snow raise the road under the structure, so the real clearance can be lower than the posted figure.
-
50. Before raising the hood to inspect the engine compartment, what should you do?
Show answer
Answer B: Shut off the engine, set the parking brake and chock the wheels if needed
The engine compartment is inspected with the engine off and the vehicle secured so nothing can move or turn while your hands are inside.